Friction shock absorber



Feb. 4, 1947. E lgnat-nn! FRICTION SHOCK ABsoRBER Filed Feb. l0, 1944 Zhi/enfui Geo/ge ELDai/r,

Patented Feb. 4, 1947 FRIc'rIoN snooicnsoitna George E. Dath, Chicago, Miner, Inc., Chicago,

` Delaware Ill., assignorto W. H. Ill., a corporation of Application February 10, 1944, seria1N0;521,7s5

7 Claims. 1

This invention relates to improvements in friction shock absorbers, especially designed for snubbing or dampening the action of the springs of railway car trucks.

One object of the invention is to provide a friction shock absorber adapted to replace one or more of the spring units of a truck spring cluster of a railway car for snubbing the action of said cluster.

Another object of the invention is to provide a friction shock absorber of the character indicated, comprising relatively sliding friction elements, including a tapered friction post and friction shoes embracing the post and slidable thereon, wherein the frictional contact is maintained by spring means which yieldingly opposes sepavration of the shoes by the tapered post and yieldingly resists relative movement of the post and shoes lengthwise with respect to each other.

AA more specific object of the invention is to provide a shock absorber, as set forth in the preceding paragraph, wherein the shoes are providedwith foot members which support the shoes for tilting movement, and the spring means bears Ion a follower ring which exerts pressure on the foot members of the shoes to resist the Ytilting movement of the shoes produced by the spreading action of the tapered post.

Other objects of the invention will more clearly appear from the description and claims hereinafter following.

In the drawing forming a part of this specification, Figure 1 is a transverse vertical sectional View of my improved shock absorber. Figures 2 and 3 are horizontal sectional views, corresponding respectively 'to the lines 2-2 and 3-3 of Figure l, the spring resistance being omitted in Figure 3. Figure 4 is an elevational. View of the left hand shoe in Figure 1, looking from right to left in said figure.

My improved friction shock absorber comprises broadly a friction post A; two friction shoes B and C; a spring follower ring D; and a spring E.

The friction post A comprises a relatively wide, platelike portion I0, which forms the post member proper, having a laterally projecting, annular flange at the upper end, which is in the form of a heavy disc having a downwardly oifset, central portion I2, which is formed with a central depression or recess I3, adapted to receive the usual spring centering projection of the top spring plate for the truck spring cluster of the railway car. The plate I0, which forms the post proper, depends from the disclike portion I I and is tapered downwardly, as clearly shown in Figure 1, thus presenting flat friction surfaces III-I4 on opposite sides thereof, which converge toward each other in downward direction. At the bottom end, the post is provided with laterally, outwardly projecting, heavy flanges |5|5 at the friction surface sides thereof, forming, in eiect, a head member presenting upwardly facing, horizontal stop shoulders.

The two friction shoes B and C are of identical design, each shoe comprising an upwardly extending, inwardly inclined arm Il and a base member I6 at the lower end of the arm. The arm I'I isV laterally, inwardly enlarged at its upper end, as indicated at I8, thereby providing a downwardly facing, horizontal stop shoulder I9.. On the inner side, the enlargement of the arm of each shoe is provided with a at friction surface 20 engaged with the friction surfaces |4 at the corresponding side of the post A and correspondingly inclined thereto. The outer side of the arm is transversely rounded, or curved, as indicated at 2|. At the upper end, each arm has a at, transverse abutment face 22, adapted to engage with the offset I2 of the platelike section of the post A to limit relative approach of the post and shoes in lengthwise direction.

The base member `I6 of each horizontally disposed, inwardly extending section 23 at the lower end of the arm Il, a horizontally disposed section 24 extending from the section 23 and downwardly offset with respect to the latter and terminating in a depending foot portion 25. The sections 24-24 of the two shoes Bf and C are angularly cut out, as indicated at 26 in Figures 3 and 4, so as to interiit, said cut out portions providing transverse shoulders 21-21 on said shoes, respectively, which lie in the central transverse vertical plane of the post A. These shoulders prevent separation of the shoes at their base portions laterally outwardly away from each other. The foot portion 25 of each shoe extends laterally beyond the inner side of the cut out portion of the section 24 of the base portion I6, as clearly seen in Figures 3 and 4, and has a rounded bearing surface 28 at the upper outer side thereof, for a purpose hereinafter described. The foot y25 is tapered in downward direction and presents a substantially flat, bottom, end face 29. The corner at the outer side of the face 29 forms a fulcrum 3|! on which the foot 25 is adapted to rock or pivot. The spring follower plate or ring D'comprisestwo like sections 3| and 32, each section being of substantially semicircular form. Each section 3| and 32 has an upwardly oiset portion 33, said oiset portions 33-33 of the 'two shoe comprises a sections together forming a centrally disposed, hollow, cylindrical boss on the spring follower plate D. Each offset 33 is angularly recessed at the inner side, as indicated at 34, the recesses 34-34 of the two sections 3| and 32 of the fol- 5 lower plate D together defining a rectangular opening at the .center of said follower. The inner side of eachoifset 33 is `undercut at said'openiiig of the follower to provide a bearing seat 35 for the foot 25 of the corresponding vshoe B or C, said gli)l seat having a downwardly and inwardly facing, rounded bearing surface 36 engaging over the rounded bearing surface 28 9 f vsaid foot.A

In the assembled condition of the shock ab,- sorber, the two shoes B and C are disposed at l5 opposite sides of the post A with 4 their base per,- tions I-IG interengaged, as shown in Figures 1 and 3, and the split follower plate D is ,engaged over the foot members 2 5-25 of said shoes with the ,mended bearing snif-,ases 36e-.3.6 engaging 20 the surfaces zal-2,8 'of' the .members 2.5..-.255 iiis be Lerident the ASininjfeildwei niais D thus is beth the nienbeis ,25-{25f'and the snpt on'whijch no nibers 25T-[2,5 are fuif cj med, .whieh lsdpndit, ,in the present instance, 25 is lbwer spring plate'y of the truck spring cluster of a railway Car. A TllQSpT-.llg COmp-fsesa `heavy ,coil surround- ,ineinander A and 'ShQeSB and C; bearing at it ,top sand `bottom ends, respectively', on the 30 teiike 'Sentieri' 1;! Of'tiie 'nest/A andthe Spring erni'ate or rin's'D- The 'spring E' isiplrefu y under initial eompression; Myimprp ed hol; abso ber is substituted for beine ,in'teirinsed .between the usual top .itdni Spiting plates of Said Cluster, the ,base seetion l] of `the ,D QSt A `bearing idp Spring plata and the ,font members H sBjand ,C Vand'the ,follewe'r Vplate VD 40 be @CHOIR Spring plaid assegni ng nthe parts of my improved shock absorben Shoes are niet Connected with each 'dtiieby'intereng 'ngtnebase 'portions thereof. The isectionalfoilower ring `or vplate D is then 45 engaged around the. base nertionsdf the Shoes 'Sli 'en "2d-#23 0i said foot portiens 25.-25. The ,Spring Eis next piaeed around the ,post and shoes and seated 4on the follower plate D. The @dei A zisthen applied blvinsertine the saine downwardly within the cQil of the spring E and entering thename Abetween the shoes B `and C, 55 which are'temporarily spread apart at their upper ends 1to admit the enlarged head portion Qf the pest therebetween. The 4post is Yforced downwardly `until the stop 'flanges 'l5-@I5 pass Abeyond Ashoulders ml-9 of `the shoes and engage 60 underneath said shoulders, The parts are lthus brought 'to the completely assembled lcondition showr'i lin Figure l1, with the shoulders l 9--19 ovehanging the `flanges t5-I5 of the post, thus limitinglen'gtrhwise separation of the post and 65 shoesl'and fielding Athe Vmechanism assembled.

{Flieg-Operation di the improved Shack absorber iS tasiiaiiowg linen the einstein 0f Springs df the railway kcar truck being compressed between the eniin's-idlidwer plaies 0i the irnksspf'inas, 'die '7o friction postA and `the rictionshoes ,B and CK are moved rel tively toward each other in lengthwise direction, against the resistance of the Ysi ing In, Due te tneianer O f the post, the

'p'iating ends 'of' the shoes are spread apart 75 @fthe spring .unitsf a yand; spring et 4 and the shoes tilted on their foot portions 25-25 fulcruming at the edges 30-30 thereof'on the lower spring follower plate of the spring cluster. This tilting movement of the shoes is resisted by the spring E, which bears on the plate or ring D, which, in turn, bears on the-upper sides of the foot Tmembers `of the shoes. The lliluired fric- .tionai resistance .in snub the action nf .the tinck springs is thus produced between the friction surfaces of the post and shoes. Upon the spring follower plates of the truck springs being moved fanart during recoil of said springs, the expansive `action of the spring E restores all of the parts tp the nor-mal 4release position shown in Figure l, separation ,of the post and shoes in lengthwise direction being limited by engagement of the stop flanges |5-l5 of the post with the shoulders |9-1L9vvof the shoes.

I have herein shown and described what I now ennsidei the preferred 'manner nf earning-911i .iny invention nii die saine .is :merely iiinstiatire and I contemplate all chansen and indd.,` aan that come within the scope of thevclaiins endledhereto. I claim:

.1- 'In frieden .sneek absinthe?, the edinbinatien with a iirietion pnsi; df iiieiidn nenes vat opposite sides of the mechanism, said'shoesheinbracing Said .nasi at Opposite sides., .eaendf 'Said SHOES hail/mg @n inlleal has? portfm? .at me eige of the -v-iriecljianisnl opposite to'Y which the shoe is 'disposed andvsunportedwfor vpivotal ,Inovexnez d at said last named side of the Vmechanism, said post and shoes being movablelengthwise with'respe'ct to 'each otherfa follower bearing on said shoes 'above the -pivotsithereoff ;v land spring -means hoplposing relative'long'i-tudinal movement of said post fand `shoesjtov'vard each other, said spring means yieldingly forcing` said Vfollower against said shoes to resist swinging `.movement of 'the latter away from said post.

A2. In -a 'friction ,shock absorber, the combination Awith a ,tapered friction post; .of interengaged friction shoes embracing said post at opposite sides, eachshoe having Va friction surface engaging Aone side of the post, jand -a Alaterally projecting-.base portion, said :ibase portion hex# tending away from the ifricti'on surface side of the/shoe Lto the opposite side of the-mechanism, and .havingua depending -'foot portion fulcrumed at its lower end, said post and shoe'sibe'ing movable lengthwise with :respect .to ,each other, said post` `'and vshoes having' Ashouldered engagement with keach other Vto .li-mit .relative longitudinal separation of :the same; a follower `bearing on said shoes above the 4fulcrurns .ithereofq and spring means reacting 1 between (said :follower and postfto oppose relative longitudinal .movement ofsaid shoesvand'post toward .eachother and yieldingly resist rocking of the shoes away ,from said post.

r3. :inra friction Yshock absorber, :theeombination-,with a tapered-,friction ,.post of friction shoes respectiyely ,haying -upstanding portions fembracf.- ingv said ,post -atopposite sides, :eachf said shoes having fa laterally 'projecting :base portion yextending 'laterally inwardly from said upstanding portion and :having `a .depending lfoot portion at its extremity vmounted .for rocking movement at itsflower Send, vsaid shoes and post -being .movable lengthwise `toward each other; a Afollower ring having camming engagement withthebasepor- .iiQnS'f endende# and anfing ni'eans one in? relain/.eildngi,.indinai,inni/einden said Slides and been ing von the 'follower ringV to yieldingly resistoutward swinging movement of said shoes away from said post.

4. In a friction shock absorber, the combination with a tapered friction post; of tiltable friction shoes embracing saidpost at opposite sides, each shoe having a base portion extending laterally therefrom toward the center line of said post and beyond the same, said base portions having depending foot members at their eX- tremities fulcrumed at their lower ends, said shoes and post being slidable lengthwise with respect to each other; a spring follower having camming engagement with said shoes to resist tilting thereof away from said post; and spring means opposing relative movement of the shoes and post toward each other in lengthwise direction, said spring means bearing on said spring follower to yieldingly resist tilting movement of the shoes.

5. In a friction shock absorber, the combination with a tapered friction post; of tiltable friction shoes embracing said post at opposite sides, each shoe having a base portion projecting laterally outwardly away from said shoe toward the center line of the post and beyond lthe same, said base portions having depending foot members rockably supported at their lower ends, said shoes and post being slidable lengthwise with respect to each other; a follower ring having camming engagement with said base portions of the shoes to oppose separation of the same; and spring means opposing relative movement of the shoes and post in lengthwise direction toward each other, said spring bearing on said follower ring to yieldingly resist camming action of the shoes and ring and tilting movement of said shoes.

6. In a friction shock absorber, the combination with a top follower member; of a tapered post depending from said member; a pair of friction shoes embracing said tapered post at opposite sides, each shoe having an upstanding section and a base portion extending laterally from said upstanding section toward the center line of said post and beyond the same, each shoe having a depending foot at the outer end of its base portion, said foot portion being fulcrumed at its lower end, said shoes and post being slidable with respect to each other in lengthwise direction; a cam member bearing on the base portions of said shoes; and spring means surrounding said shoes and post and `bearingrat its opposite ends on the follower member and the cam member, said spring means opposing relative longitudinal movement of said post and shoes toward each other and tilting movement of the shoes away from said post.

'l'. In a friction shock absorber, the combina-` tion with a tapered friction post having laterally projecting stop iianges at its lower end; of tiltable friction shoes at opposite sides of the mechanism embracing said post at opposite sides,

each shoe having a shoulder overhanging theV stop ange at the corresponding side of the post to limit relative separation of the shoes and post in lengthwise direction, each shoe having a base portion projecting laterally away from said shoe toward the opposite side of the mechanism, and a foot depending from said 'base portion and fulcrumed at its lower end, said shoes and post being slidable lengthwise with respect to each other; a two piece follower plate embracing said base portions of said shoes and having camming engagement with the foot portions thereof; and spring means opposing .relative movement of the shoes and post in lengthwise direction toward each other, said spring means bearing on the two piece follower plate to oppose camming action between said shoes and follower plate and thereby resist tilting movement of the shoes away from said post.

GEORGE E. DATI-I.

REFERENCES CITED The following references `are of lle of this patent:`

UNITED STATES PATENTS record in the British Feb. 1B, 1914 

